How to add an alert to switch toggle for multiple answers? - ios

Question

I created a Quiz app. There is one question with five answers, where the user can choose one of them. However at the moment it's possible to choose more than one answer. How can I add an alert (UIAlertController) and a restriction so if the user has already chosen one answer and tries to choose a second one ?
var questionIndex = 0
var answersChosen: [Answer] = []
func updateUI() {
let currentQuestion = questions[questionIndex]
let currentAnswers = currentQuestion.answers
let totalProgress = Float(questionIndex) /
Float(questions.count)
numberOfQuestion.text = "\(questionIndex+1)/5"
// navigationItem.title = "Вопрос - \(questionIndex+1)"
mainQuestion.text = currentQuestion.text
progressBar.setProgress(totalProgress, animated:
true)
updateMultipleStack(using: currentAnswers)
}
#IBAction func multipleAnswerButtonPressed(_ sender: Any) {
let currentAnswers = questions[questionIndex].answers
if firstSwitch.isOn {
answersChosen.append(currentAnswers[0])
}
if secondSwitch.isOn {
answersChosen.append(currentAnswers[1])
}
if thirdSwitch.isOn {
answersChosen.append(currentAnswers[2])
}
if fourthSwitch.isOn {
answersChosen.append(currentAnswers[3])
}
if fifthSwitch.isOn {
answersChosen.append(currentAnswers[4])
}
nextQuestion()
}
func updateMultipleStack(using answers: [Answer]) {
firstSwitch.isOn = false
secondSwitch.isOn = false
thirdSwitch.isOn = false
fourthSwitch.isOn = false
fifthSwitch.isOn = false
firstQuestionLbl.text = answers[0].text
secondQuestionLbl.text = answers[1].text
thirdQuestionLbl.text = answers[2].text
fourthQuestionLbl.text = answers[3].text
fifthQuestionLbl.text = answers[4].text
}
override func prepare(for segue: UIStoryboardSegue, sender:
Any?) {
if segue.identifier == "ResultSegue" {
let resultsViewController = segue.destination as! ResultViewController
resultsViewController.responses = answersChosen
}
}
}

Answer 1

The approach I'd take would be to separate the user's selection of an answer (UISwitch collection) from processing the selected answer(Submit Answer button). This would allow the user to change their answer. The previous selection is automatically cleared. The answer is final when pressing a "Submit Answer" button (not shown).
In this code example, the switches are set as an IBOutlet collection. The tag on each switch is set from 0 to 4. All the switches are connected to an IBAction called switchPressed. A variable called selectedAnswer is used to identify the user's final picked answer when the "Submit Answer" is pressed.
#IBOutlet var switches: [UISwitch]!
private let noAnswer = -1
private var selectedAnswer = -1
#IBAction func switchPressed(_ sender: UISwitch) {
// Check if user turned off switch
guard sender.isOn == true else {
selectedAnswer = noAnswer
return
}
// Get user's answer and set all switches
selectedAnswer = sender.tag
switches.forEach { $0.isOn = false }
sender.isOn = true
}
#IBAction func submitAnswer(_ sender: UIButton) {
guard selectedAnswer > noAnswer else { return }
// use selectedAnswer to process answer and go to the next question
answersChosen.append(currentAnswers[selectedAnswer])
}

Answer 2

You could store all the switches in an array named Switches for example and then run a for loop to check if more than one is selected when checking answer.
var count = 0
for switchToggle in switches {
if switchToggle.isOn {
count += 1
if count > 1 {
//Print Warning "only select one"
}
} else {
//append answers
}
}
you could also use this to have multiple answers for certain quiz question
For the warning, you have different options you could use. You could use UIAlertController to display a warning if more than one button is selected but this could become annoying for the user after a while.
Another option could be to use a UILabel which warns the user to only pick one answer. You could animate the label to fade away after a few seconds.